text:
How can I become familiar with flight rules specific to Canada when flying there from the United States?
As a US licensed and trained pilot, I know I can fly into Canada, but are there are airspace rules that are different from the American system. Is there a Canadian rules test or conversion you can or should do, or should I just expect to fly in Canada by the exact same rules and procedures as in the United States?

In the specific case of Canada, AOPA and COPA have a lot of information aimed at US pilots. AOPA has a complete guide on documents, customs etc. and COPA has a page with more information, which includes this remark:

The flying rules are almost indistinguishable - reading the COPA guide
  should keep you legal and out of trouble. Make sure you get a Canada
  Flight Supplement (CFS) and some VNCs (Canadian equivalent to your US
  sectionals), that will allow you to navigate VFR safely.   IFR plates
  are available from Nav Canada as a subscription or the (sample list
  of) vendors included below. (by mail order)

The guide is free but available to AOPA/COPA members only.

That's great! Thanks!

Your second link is broken, plus there are some other operational differences (for instance, there is a difference in climb/descend via clearances between the two countries that get some pilots in to trouble).

@Lnafziger Thanks, fixed!

No, you need to know the differences.
A big one is all airspace between 12500 and 18000ft is Class B.
So you need either an IFR or VFR clearance.
https://en.wikipedia.org/wiki/Canadian_airspace
  Class B airspace is any controlled airspace between 12,500 ft (3,800 m) and 18,000 ft (5,500 m) Occasionally, Class B airspace exists in other locations, though this is unusual.
https://www.tc.gc.ca/eng/civilaviation/publications/tp15048-menu-5859.htm
Class B     Controlled low-level airspace (above 12 500 ft ASL, up to 18 000 ft ASL); IFR and CVFR only.


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Is air to air refuelling possible at "cruising altitude"?
When an aircraft uses air to air refuelling are there constraints on the maximum altitude this can take place at?
For instance I'm guessing that a Boeing Globemaster when on a long journey would cruise at 8,000m or higher (Wikipedia says service ceiling is 14,000m / 45,000'). Is there any reason why air-to-air refuelling can't take place at that sort of height?
I'm wondering whether there's something about the lack of air pressure that makes it problematic to transfer fuel or the speeds that must be used for the transfer are not viable at very high altitudes.

The main limitation is that the receiver needs to have enough excess thrust available to be able to precisely maintain formation on the tanker. Near the service ceiling, you typically don't have a lot of excess thrust, so refueling happens somewhat lower than that.  Since fighter generally have more excess thrust at a given altitude than a transport will, they can refuel at somewhat higher altitudes.
Other than wanting to have enough excess thrust available to accelerate forward in the event of a "breakaway" call, tankers don't have particular limitations that I'm aware of, though I've not flown those. (I'd assume being right at the limits of IAS / TAS isn't particularly comfortable for a tanker, so at least something below their service ceiling, but I don't know what that limit is.)
Pumps, rather than differential pressure, move the fuel, so that system is unlikely to drive any altitude constraints.
It's common to hear refueling happening in the mid-20's over the U.S.  How much that's driven by airspace availability vs by performance, I don't know.

Totally ignorant on this but wouldn't an aircraft be easier to control in denser air? This manoeuvre seems involve some precision flying and I would expect ease of control to be an issue.

@RoyC: Thicker air would give you more control authority for the same deflection of a control surface at the same true airspeed, but IDK if that makes precision formation stuff easier.  You want to make really small adjustments to angle to guide the plane onto the refuelling tether; if it takes larger actual control inputs from your hand to do that, it might actually help.

@Peter Cordes Makes sense, thanks for clearing that up for me.

@RoyC: According to @Efe's answer, high altitude refueling would often mean lower indicated airspeed, so the small planes actually are more sluggish.  So my assumption of near-constant IAS with altitude apparently wasn't right, and it makes sense that having the plane seem to respond more slowly to control inputs would make things harder for the pilot.  Maybe my guess about making larger control inputs isn't how it works.

From the NATO website describing the a330mrtt:

The Airbus tankers will be able to refuel a wide range of aircraft
such as NATO AWACS surveillance planes; F-35, F-16 and Rafale fighter
aircraft; and C-17 transport planes. Refueling can be performed at an
altitude up to 35,000 ft while cruising at speeds between 180 knots
and 325 knots.

The A330mrtt has a service ceiling of 42,700ft so refueling is constrained to occur below the maximum cruising altitude of the tanker, but not by much.
The service ceilings for the F35, F16 and Rafale are all above 50kft, so fighters are not the constraint. The AWACS service ceiling is 35kft, while the C17 goes to 45kft. The website did not disclose whether each class of aircraft had a different limit.
Fuel is transferred by pump and is independent of speed or altitude.
In response to comments:
The MRTT designation stands for Multi Role Tanker Transport; intended for uses in addition to tankering. It is based on the A330-200 but uses the A340 wing which has reinforcing for two outer engines, which are swapped out for Cobham fuel delivery pods. Standard passenger and cargo decks cover the transport part of the designation; tankering fuel is only carried in the wings unlike the KC10 which also has aux tanks in the cargo hold.

Why does it have windows? Isn't that where the fuel goes?

@DanSheppard dollars to doughnuts it’s a commercial variant, and removing the windows costs more not less. If you want a real answer, ask a real question :)

Some (if not most) tankers are recycled commercial aircraft and don’t even have special fuel tanks, they just use the standard tanks.  Given that an airliner carries enough fuel for a flight of several thousand miles, it’s plenty to keep a few small planes supplied.

@DanSheppard Tankers often are also used for troop/supply transport. The passenger deck is still available. See this related answer: https://aviation.stackexchange.com/questions/15091/how-is-fuel-stored-in-a-tanker-aircraft

@DanSheppard the RAF A330MRTTs are operated by AirTanker, which uses them for passenger transport when they aren't being used by the military. https://en.wikipedia.org/wiki/AirTanker_Services

I'm now wondering what the inside looks like. I'd kind of imagined they were like road tankers with a cylinder of fuel making part of the body. (I know nothing about these things!) I guess it's not like that, then.

@DanSheppard, I've been inside a couple (KC-135 and KC-10) at airshows.  The tankage is basically the bottom third to bottom half of the fuselage; the upper part can be used for cargo (self-loading or otherwise).

@DanSheppard the inside of an MRTT looks the same as a regular airliner as the fuel they give away is contained inside the standard tanks. Since they don’t take pax or freight during refuelling missions they can just fill it up with gas to give away rather than balancing fuel / freight. Indeed the UK VIP jet for the Prime Minister is a refueller jet with a modded interior and fancier paintwork.
https://www.youtube.com/watch?v=44eC4XETigQ

Airliner-type aircraft fly close to stall speed at cruise altitude as their maximum speed in terms of Mach (Mmo) and their stall speed are within 15-20 knots to each other. Tankers cannot fly any faster (excluding buddy tanking, which generally happens at much lower altitudes and in the vicinity of the carrier), so fighters are also constrained to fly close to their stall speed to stay with the tanker. Fighters (well all aircraft actually) are sluggish to maneuver at that speed and this makes refueling more difficult. Furthermore, the weight added to the receiver during refueling more strongly affects the behavior of the receiver at low airspeeds.
For this reason, refueling is normally done at lower altitudes, to enable the tanker to fly at higher indicated airspeeds to keep the receiver aircraft further away from stall.
The SR-71 used to refuel very close to its stall speed, while the KC-135Q tanker flew at Vmo at an altitude where Mmo was not a problem. Despite this, to stay with the tanker and not stall, the SR-71 had to light one afterburner when its tanks were close to full and refueled with a sideslip.

At cruise, an airliner may have 15-20 knots between MMO & the low speed buffet limit, but that low speed buffet is significantly above the actual stall speed.

True, what I meant is that the tanker has only 15-20 knots to play with. The fact that a tanker won't actually stall doesn't mean that they'll fly it in the buffetting region to help a slow receiver airplane catch up.

If they fly on the buffet wouldn’t that make it turbulent for the receiver?

As long as they've wiped the buffet clean... sorry that was too easy. I don't believe so, the receiver would be further below the tanker's wings so it would most likely be away from wingwash.

When I was in a KC-130 Squadron we refueled CH-53 helicopters and F-4 Phantoms.  (Not at the same time!)  I was in the back so I didn't pay attention to the airspeeds, but obviously they were quite different...

Exactly. That's why the KC-130 flew below economic cruise altitude, to fly slow enough for the Stallion and fast enough for the Phantom. This leeway is impossible at cruise altitude.
Also, I believe the KC-130 had the ramp open during refuelings, doesn't that by itself rule out refueling above 13000 feet?

No, ramp open was definitely not SOP.  Possible, and makes for cool photos, but doors were closed and we flew high and fast while refueling jets.

Some of the answers have hinted at a bit of a problem in the question, but I think it's worth bringing it out a little more clearly: whose cruising altitude do you care about?
When a KC-135Q is refueling an SR-71, it's flying what for it is high and fast--but for the SR-71 is fairly low and slow.
When a (non-Q) KC-135 is refueling an A10, we get pretty much the opposite situation. The A10 is flying high and fast (for an A10)--but the 135 if flying low and really slow (as in: drop not only the flaps, but also the landing gear to add drag).
As others have also alluded, you do need more maneuvering than just normal flying so as a starting point, take the aircraft with the lower cruising altitude, and subtract something like 20% for a starting point on a reasonable altitude for refueling.

Great point Jerry, same for C-130s. Especially as the performance gets worse the more fuel you onload! :)

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Do glider pilots have to wear parachute in countries where mandatory even if flying with a foreign glider?
Today I saw this video on Vimeo that shows a pilot flying a new solar glider (N- registered aircraft) in Italy without wearing a parachute (I believe in US is not mandatory).
Actually here in Italy it is mandatory to wear parachutes in gliders (at least I- registered). In our club we carry them also on our D- gliders but I don't know if it is also mandatory.
What is the scope of local regulations for foreign aircrafts? Do they have to comply also with this issue or is it up to the user, since it is a factor that only affects him?
Please feel free to edit my question with better words if my text is incomprehensible.

I can't really answer your question, but a little background:  FAR §91.307 says: "(c)Unless each occupant of the aircraft is wearing an approved parachute, no pilot of a civil aircraft carrying a person (other then a crewmember) may execute an intentional maneuver that exceeds -
(1) A bank of 60 degress relative to the horizon;
or
(2) A nose-up or nose-down attitude of 30 degrees relative to the horizon."
There is more to it, read it up if you want.
Gliders usually exceed these limits, so you should have a parachute in an N registered glider.

I wouldn't be surprised that the country of registration determines most of the applicable regulation. Regarding air safety overall this is the country of flight, but this may be intended to public safety, not pilot safety.

In general, you take the most restrictive regulation of the country of registration, the country of licensing and the airspace. There is really no general answer to this - you have to study all three sets of regulations.

@howardhughes I agree with your reasoning, but gliders are designed for +5.6 gs. Also, the seat pan is shaped such that the head is too low without a parachute supporting your behind. However, in small cockpits is is sometimes helpful to place the chute behind the head - helped me in some older types.

For US (N-reg aircraft), this is defined in 14 CFR 91.703, Operations of civil aircraft of U.S. registry outside of the United States. It says:

(a) Each person operating a civil aircraft of U.S. registry outside of
  the United States shall—
(1) When over the high seas, comply with annex 2 (Rules of the Air) to
  the Convention on International Civil Aviation and with §§91.117(c),
  91.127, 91.129, and 91.131;
(2) When within a foreign country, comply with the regulations
  relating to the flight and maneuver of aircraft there in force;
(3) Except for §§91.117(a), 91.307(b), 91.309, 91.323, and 91.711,
  comply with this part so far as it is not inconsistent with applicable
  regulations of the foreign country where the aircraft is operated or
  annex 2 of the Convention on International Civil Aviation; [...]

That suggests that in most cases the pilot should follow the foreign (Italian) regulations:

91.703(a)(2) says you have to follow foreign regulations on "flight and maneuver"
703(a)(3) says you should (mostly) follow part 91 unless it's "inconsistent" with the foreign regulations

It all seems a bit vague to me, and what "inconsistent" means is probably the kind of thing that keeps lawyers busy. But also note that there are specific rules applying to operating foreign aircraft in the US. 14 CFR 91.711, Special rules for foreign civil aircraft, begins:

(a) General. In addition to the other applicable regulations of this
  part, each person operating a foreign civil aircraft within the United
  States shall comply with this section.

So foreign aircraft in the US are expected to follow US regulations as far as possible, which is consistent with 91.703: an N-reg aircraft abroad follows the foreign rules as far as possible, and a foreign aircraft in the US follows US rules as far as possible.
Since both the US and Italy are ICAO members, I would expect Italian law to roughly mirror US law on this, although that may be a dangerous assumption. For an authoritative answer, I would ask both the FAA and the Italian authorities.

Thanks @Pondlife. So as per my understanding, the guy in the video (with a N-registered glider flying in Italy) would legally have had to wear a parachute? (Just for info, in US is only mandatory for aerobatics I believe, in Italy is always mandatory).

@maximusboscus If wearing a parachute is included in "flight and maneuvers" then yes, but since that isn't defined clearly in the regulations I don't really know. My guess is that "flight and maneuvers" is intended to mean that you should follow local rules on flight paths, altitude, speed etc. but what happens inside the aircraft is still governed by the US regulations. It's like driving from Italy to the UK: you must drive on the left and obey the local speed limits, but no one says you must switch your GPS to English or change the speedometer to miles per hour.

Thanks for the response and funny comparison haha. I am trying to find the italian regulations about the use of parachutes in glider but until now no success :(

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How does the line of thrust affect longitudinal stability?
I’ve been studying Pilots Handbook of Aeronautical Knowledge FAA-H-8083-25B and on p 5-17 they talk about thrust line and stability. Can someone explain why the moment changes when thrust is applied?

Power or thrust can also have a destabilizing effect in that an
  increase of power may tend to make the nose rise. The aircraft
  designer can offset this by establishing a “high thrust line” wherein
  the line of thrust passes above the CG. [Figures 5-26 and 5-27] In
  this case, as power or thrust is increased a moment is produced to
  counteract the down load on the tail. On the other hand, a very “low
  thrust line” would tend to add to the nose-up effect of the horizontal
  tail surface. Conclusion: with CG forward of the CL and with an aerodynamic tail-down force, the aircraft usually tries to return to a safe flying attitude.

You have two different questions.
Question 1

Can someone explain why the moment changes when thrust is applied?

The graph below illustrates the forces from a propulsor and its relative location to the airplane CG. As illustrated, the thrust line is below the CG. Therefore, as power is increased, more thrust is generated, and you get a nose-up moment.

Image ref: Etkins, Dynamics of Flight
Question 2

How does the line of thrust affect longitudinal stability?

This is a much more interesting question. The explanation below may be a little dry.
a. Longitudinal stability
Longitudinal stability, by the letter of the law, is defined by whether increasing elevator control force is needed to change and maintain an airspeed, and whether the aircraft returns to the same airspeed with elevator released. From an engineering perspective, it can be expressed as a single criterion (see Ch.6.5, Etkins, Dynamics of Flight):
$$\frac{dC_m}{dC_L}\bigg\rvert_{steady}<0$$
where $C_m$ is the total pitching moment coefficient about the CG and $C_L$ is the lift coefficient of the airplane. This expression states that, with a constant stick force, the pitching moment must be nose down when lift increases from the trim point (i.e. airspeed decreases from trim speed), and vice-versa.
b. Thrust line effect
Now let's look at the pitching moment contribution from a propulsor ($C_{m_p}$):
$$C_{m_p}=C_T\frac{z_p}{\bar{c}}=\frac{T}{1/2\rho V^2S}\frac{z_p}{\bar{c}}$$
where $C_T$ is the thrust coefficient, $\bar{c}$ is the reference chord length, $T$ is thrust, $\rho$ is air density, $V$ is airspeed, $S$ is reference area, $z_p$ is the thrust line offset as shown in the picture above.
To keep matter simple, I'm going to assume that:

We are dealing with a jet engine here such that the thrust stays constant (similar overall conclusion is drawn for a constant power propeller; for detail, see Ch.3.4 of Etkins, Dynamics of Flight) and,
Lift is equal to weight such that:

$$C_{m_p}=\frac{T}{W}C_L\frac{z_p}{\bar{c}}$$
With a straightforward differentiation with respect to $C_L$, we get:
$$\frac{dC_{m_p}}{dC_L}=\frac{T}{W}\frac{z_p}{\bar{c}}$$
As you can see, the sign of this quantity is dependent on the thrust line offset. A positive offset (i.e. thrust below CG) provides a destabilizing effect ($\frac{dC_{m_p}}{dC_L}>0$), whereas a negative offset (i.e. thrust line above CG) provides a stabilizing effect.

There is a general rule: don't trust "Pilot's Handbooks" when they talk about aerodynamics. More often than not, they are full of misconceptions and, at best, oversimplifications. In your quote, for example, the conclusion has nothing to do with the preceding text.
But the question is fair. Thrust line can affect stability, but we need to define what exactly we understand by that.
Stability as such is a negative reaction to a disturbance: a disturbance of a particular defined kind must cause a reaction which negates the original disturbance. Usually, we restrict the analysis to relatively small disturbances, when reactions are more or less linear.
Longitudinal stability, in a broad sense, describes any longitudinal motion. For airplanes this involves pitch or speed. (Altitude is a different axis and even a different frame, although we'll need to consider it in some cases). These are linked but different motions, and we can talk about them separately to some extent. It just happens that for most airplanes, the characteristic times of these angular vs linear motion is so different that we can very well analyse them independently. The heavier the airplane (and/or higher its wing loading), the better it holds. Even for GA airplanes it's still largely true.
In a strict sense, when aircraft designers (but not pilots) talk about "longitudinal stability", they mean the short-period pitch stability, or more accurately, angle of attack (AoA) stability. This means that when AoA is disturbed (by a gust or control input), a moment immediately arises that counteracts this AoA change (which is done via pitch change).
The mechanism behind AoA stability involves purely aerodynamic moments/forces. (The explanation involves the concepts of neutral point and moment derivatives). Notably, it does not involve thrust nor airspeed. Both of them change too slowly compared to AoA/pitch and so play practically no role in longitudinal stability per se.
But when it comes to airspeed stability, with which pilots are more intuitively familiar, the situation is different. Airspeed stability is linked to AoA stability via an indirect mechanism that Robert already roughly described in his answer: "increased thrust, increased speed, increased lift, plane rises vertically, vertical "up" pushes tail down, pitch changes". The important result is that a statically stable (read: AoA stable) aircraft will also be stable in speed. But even that holds only if drag doesn't grow faster than lift; that is, on the front side of the power curve. (Pilots know it very well). At high (but pre-stall) AoAs, the airplane will remain stable in AoA but will become unstable by speed.
Technically, this is still speed stability, not thrust stability. We are not concerned how airspeed changed: thrust, gust, dive, whatever. A statically stable airplane will try to pitch up and climb as a response to increased airspeed, slowing down as a result.
But when we analyse speed changes as a specific result of thrust changes, other factors come into play. Namely, apart from speed, changing thrust can disturb the moment balance of the airplane. In general, multiple effects can be important here, not only the location of line of thrust with respect to CG, but also with respect to 'centre of drag'; and the changed slipstream may cause aerodynamic changes. Either way, it may happen that these extra moments may augment or negate the natural tendency that comes from AoA stability.
For simplicity, let's analyse a few obvious cases of reaction to increased thrust (leaving everything else unchanged, particularly trim).

Thrust is in line with CG. The airplane will start to climb (or reduce descent) and will settle on the same AoA and roughly the same speed.
Thrust line below CG (the case of most airliners with underwing engines). This will produce an added pitch-up moment, which will cause the airplane to slow down more than necessary, despite the added thrust! This is an unstable condition. It can be particularly nasty in go-around situations. How do we fly it? Luckily, unlike AoA, the changes are slow enough for pilots (let alone autopilots) to react with active trim changes.
Thrust line above CG. This is the opposite of the above and, in moderate amounts, can have stabilising effect and easier trim changes. The airplane will settle at a higher speed, which is presumably what the pilot wants (despite the "power controls altitude" mantra). When the line is too high, the airplane may even descend and accelerate more than necessary, until the aerodynamic moment balances out the thrust moment, but overall the condition is stable. (Note that in most cases thrust starts to fall with increased speed, which helps to find the balance).

As a conclusion:

In a strict sense, line of thrust (and thrust as such) does not affect longitudinal stability per se; that is, the AoA stability.
However, it does affect airspeed stability, which many pilots understand as longitudinal stability.
It certainly affects trim changes, which, again, pilots perceive as a measure of longitudinal stability (not entirely without reason).

"The important result is that a statically stable (read: AoA stable) aircraft will also be stable in speed." May I disagree? Speed stability disappears at high angle of attack, on the back side of the power curve. While a statically stable aircraft will return to its old angle of attack, it will not return to its old speed when flown below minimum power speed because drag increases when the aircraft slows down further.

You are right, of course; I was just thinking about the 'normal' situation. I'll add a note.

"The important result is that a statically stable (read: AoA stable) aircraft will also be stable in speed ." That's not accurate. In transonic regime, AOA stability does not guarantee speed stability. That's why designers assess speed stability rather than AOA stability in detailed design and certification.

True, but it already gets too complicated for those who learn by 'pilots handbooks'...

Figure 5-26 is good example of the result of applying a torque (F x lever arm) around the center of gravity.  The effect is the same as applying aerodynamic torque, you get rotation.  This is why an engine mounted "through" the CG will not have this effect.  It should be noted
that drag effects are ignored in this question, so we may consider 5-26 as the result of a CHANGE in THRUST.
EDIT:  UPDATE:  (keeping reading, keep learning)
The thrust line is actually balanced with center of frontal drag.  Literature probably should be worded as such.  The concept that all thrust torques rotate around the CG may be better defined as the net thrust/drag torque.
Thrust line interacts proportionally with tail down force as velocity increases (from more thrust), which is why nose down thrust angle is built into engine mount to increase pitch stability.  We also may be learning that "positive static stability" (setting CG forward/down force on tail) may not be needed if directional stability is adequate, and may in fact introduce unwanted pitch up tendencies that require a larger tail to correct (or more trimming).
Figure 5-27 applies torque to the CG, indirectly, as follows: increased thrust, increased speed, increased lift, plane rises vertically, vertical "up" pushes tail down, pitch changes.  Opposite for reducing thrust.  This particular example has cruise (power and trim) as no effect.
So we may consider 5-27 as a result in a CHANGE in AIRSPEED, resulting from change in thrust.
Fortunately, the manufacturer, through experience, will mount the engine (usually a few degrees down, and a little right) to offset these effects as well as left turning tendency.
In practice, one counter-acts these effects with the elevator, and re-trims once the speed desired by changing the throttle is reached.
For new pilots, one might think using your elevator also has an effect on your longitudinal stability too, but no, please do not worry about this.
Minor changes in throttle, as in setting up a landing, do not cause noticeable changes in pitch.

Are those things really a matter of stability, or trim?

Since in reality we do not go around constantly changing our thrust, the effect (academicly) is a change in pitch (there for destabilizing pitch).  Once throttle is changed, we trim for our new speed.  A good example of this is transitioning from climb out to cruise.  We reduce pitch, reduce power (speed increases to around 100 knots from 70), hold desired altitude with elevator, then trim for cruise.  It's SOP.

Pitch (elevator) controls speed, power controls altitude.  Pilot controls pitch and power.  Don't over think it.

@quiet flyer has a good point. It can be said that this is a matter of trim rather than that of stability. It is not over-thinking; on the contrary, the 'elevator controls speed' is over-simplification. I tried to explain it in my answer.

The point here seems to be that "high thrust line" or angling thrust down makes for a more pitch stable design in regards to thrust, maybe more so than (or in addition to CG ahead of CL).  I would agree the wording could be improved.  And discussion with experienced people certainly helps see other points of view.  Maybe they write it stupid to get us to talk.

Just to add something to the already given answer and to what is stated in the pilots handbook.
Line of thrust is definitely not the whole story about the relationship between thrust and pitching moment. Actually it is only ⅓ of the whole story.
Indeed a propeller modifies the pitching moment via two other effects which are as important as the line of thrust but which are normally omitted.

A propeller basically produces thrust accelerating the airflow behind it (aka induced velocity). This airflow with increased speed (dynamic pressure) washes over the wing and impinges on the tailplane. The effect on the wing is to increase its pitching moment while the effect on the tailplane is to increase its effectiveness due to the higher dynamic pressure. The net effect of those two phenomenon is in general a nose-up moment which increases with the thrust.

Whatever the angle of the airflow investing the propeller is, the propeller tends to straighten the airflow behind it and align it with its axis, as depicted schematically in the following picture¹:

As usual, due to Newton's third law, if the propeller bends the airflow downward, then the airflow reacts kicking the propeller upward. This reaction force is termed normal force $F_p$, it is proportional to the thrust and it goes upward for positive AoA. And it obviously creates a nose-up pitching moment.

To summarize, a propeller not only creates a thrust but creates a pitching moment as well. The direction (nose-up or nose-down) of this pitching moment depends on the net effect of the line of thrust plus the effect just described in 1. plus the effect in 2. The magnitude of this pitching moment is proportional to the thrust generated by the propeller, being it bigger for bigger thrust.

¹ from Wikipedia, modified by me

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What does 'laterally aligned' mean in this description?
In the Airplane Flying Handbook there is a section on crosswind takeoffs that mostly makes sense. However, this paragraph confuses me.

Takeoff Roll
As the forward speed of the airplane increases, the pilot should only
  apply enough aileron pressure to keep the airplane laterally aligned
  with the runway centerline. The rudders keep the airplane pointed
  parallel with the runway centerline, while the ailerons keep the
  airplane laterally aligned with the centerline.

Laterally is an adverb meaning 'Relating to the direction to the side.'
Later on they use this image which shows the lateral axis.

When I take off in a crosswind in an airplane with nose-wheel steering the rudder pedals are used to keep the plane on the centerline. The ailerons are deflected into the wind to keep the windward wing from rising.
So what do they mean when they say that “the pilot should only apply enough aileron pressure to keep the airplane laterally aligned with the runway centerline”?
Edit: I don’t think they are referring to keeping the wings level as some commenters say. This image from the same section somewhat exaggerates the effect but ailerons are used to keep the upwind wing down.

I would normally use „laterally aligned“ to mean pointing along the centreline, but clearly that is described by „parallel with the runway centreline“ here, so all I believe they could mean is using ailerons to keep wings level - which, if true, isn’t a very clear way of putting it!

Not a pilot -  but definitely agree with “wings level.”

I third that interpretation...

@CptReynolds Except in a crosswind takeoff, you don’t keep the wings level. You keep the upwind wing down. And the nosewheel keeps the wings perpendicular to the centerline.

@JScarry Are you sure you keep the upwind wing down, as in pointing lower than the leeward one? Not just ensure it doesn’t come up?

@CptReynolds It’s not a lot, but as the airspeed increases the upwind wing is slightly down. In a strong crosswind you might even be rolling on just the upwind tire for a while. Similar to landing with a crosswind but not as extreme.

@JScarry - Your comment above is backwards.  You are saying that you keep the wings level in a crosswind take-off, but with no crosswind you keep wing down into the wind.

@MichaelHall In a no-wind takeoff the ailerons are neutral and the wings are level. In a crosswind takeoff the ailerons are deflected fully into the wind at the beginning of the takeoff roll. Wings are mostly level. As airspeed increases aileron effectiveness increases and the upwind wing drops. Depending on the crosswind it could be barely noticeable or a lot. As the rollout continues and you lift off you usually decrease the amount of aileron input and leave in just enough to crab into the wind and track the centerline.

@JScarry - I know that, I am a pilot.  But, please disregard... I just made a really silly misinterpretation of the way you used "except" in your comment.  My interpretation of your meaning was obviously flawed.  (I thought you meant "for all landings EXCEPT crosswind you don't keep the wings level"...)  I am the one who had it backwards!!!  :)

You don't normally apply enough aileron to lift the downwind wheel off the ground like that, although at liftoff, the downwind wheel will come off first.

It’s been a while since I had my hands on a yoke, but wouldn’t you ideally keep wings exactly level even in crosswind, and it’s only you want to err on the side of upwind wing down that makes you lower that wing?

@Cpt Reynolds  this would make a great question as it depends on aircraft wing length and setting.  A small GA high wing like a Cessna 152 you definitely "lean" into the wind to hold track, using the rudder to point.  A very large aircraft with very long wings would be risky to roll near the ground, I would imagine something more like a power-yaw crab into the wind (like the B-52?).  Plus their sheer mass and higher landing speed (relative to crosswind) helps too.  A small C 152 can be safely rolled quite a bit, so it works.

The only meaning that I can conceive of is that "laterally aligned with the centerline" is a fancy way of saying "on the centerline"—or, at least, keeping the distance from the centerline under control, so that you don't drift off of the runway.
The paragraph seems to be describing the following technique for lateral control during a crosswind takeoff:

Use the rudder to keep the heading (the direction the nose is pointing) parallel to the runway centerline.
Use the ailerons to control the bank angle so that the airplane stays approximately over the runway centerline.

The reason the Airplane Flying Handbook uses the word "laterally" here is that the ailerons are being used to control the airplane's lateral (left-to-right) motion.
Some comments speculate that the paragraph is really saying that the ailerons should be used to keep the wings level. That doesn't make sense to me; in a crosswind, if you're using rudder to keep the nose parallel to the centerline, and you're keeping the wings level, then you'll drift downwind off the runway.

This is exactly what the paragraphs following the excerpt describe, +1. See for example https://www.flightliteracy.com/crosswind-takeoff/ for the full text.

The lateral axis is the left/right axis. “Laterally aligned with the runway centerline” means: on top of the centerline. Not a very clear way of phrasing, I agree.

This thing is horribly written.  I think Tanner is correct, in that the writer is referring to using ailerons to establish a bank angle to prevent lateral drift.  But while rolling, the bank angle you can create is limited to the compliance of the landing gear.  On an airplane with wide oleo gear, this is effectively zero.  So it's really about using rudder to keep alignment and using aileron to hold the wing down.
As you lift off, the into wind aileron will cause the downwind wing to liftoff slightly ahead of the other, putting you into a very brief cross-controlled wing down condition where you will be side slipping briefly; then for a brief moment, you are using aileron to maintain lateral position.
Which you immediately remove as you center the rudder and adjust the heading into wind as required, then level the wings to climb out (except on an IFR departure where you just maintain the runway heading).
Surprising to see something this poorly worded in an official FAA publication.

"Surprising to see something this poorly worded in an official FAA publication"  -- not in the least IMHO.  See for example https://aviation.stackexchange.com/questions/53424/is-this-paragraph-about-the-dihedral-effect-in-the-faas-glider-flying-handbook , https://aviation.stackexchange.com/questions/53424/is-this-paragraph-about-the-dihedral-effect-in-the-faas-glider-flying-handbook

Can't always believe you read.  Notice the rudder deflection is also incorrect in the third picture.  This is why finding a good instructor is so important.
A cross wind take-off is in many ways a mirror image of a cross wind landing:  aileron into the wind, rudder away.  Yes, the downwind wing may rise first, and the plane is up on one wheel before lifting off, just as you would do in a cross wind landing.  No big deal.  Be on that rudder.
Some may choose to delay rotation a few knots, and then bring plane off the ground
a bit more briskly, then transition into a crab.  Some may hold the side slip a little longer.
But airspeed is most important here.  Watch it and keep climbing safely.
Cross controlled slow flight practice should give you confidence in these situations.
Remember to stay at a safe margin above stall.
Best interpretation of "laterally aligned" would probably be the same as in the air: roll into the wind to keep from being pushed sideways. So if your leeward wing comes up too much before rotation, simply ease off on the ailerons some.


text:
How much does it cost to give an airliner a fresh coat of paint?
Just a random thought I had: the weather gives a jet's paint job a battering; meaning they need to be resprayed approximately once every 5-10 years. (See How often is a passenger jet aircraft painted?)
Roughly what might a paint job for a 777 like the one shown in the YouTube video below, cost an airline?
Bonus: I believe afterwards that the weight of the plane has to be recalculated, so as not to affect weight-and-balance. How is this calculation done?

According to WallStreetJournal article, Tom Horton stated in an interview that :

A 777 paint job can cost  \$100,000 to  \$200,000, depending on the number of colors involved, and a smaller Airbus A320 can cost $50,000 or more.

@DavidRicherby thanks david. I have exactly that problem. Already edit. I have same paywall problem too but when link from google the article is okay. You may try that.

The exact colours needed are also a factor apparently. Someone from an airline maintenance department told me years ago that white paint is quite a bit cheaper than for example red paint, and that that factored heavily in the decisions of some airlines when adopting new liveries.

@jwenting You might be interested to see Why are planes generally paint white? :)

A news article that linked that video said it took Emirates Airlines 6550 hours to repaint 21 aircraft, an average of 312 hours each.  They run a round-the-clock operation, with 26-30 people working at any given time, so that translates into roughly 8500-9000 man hours to complete each plane.  If the average entry level salary there is similar to the US at \$18/hr, that's upwards of $175,000 just in labor.
And if a paint job weighs 555 lbs on a 747 (and that's after it dries – think of the lost moisture), and your spray efficiency is around 50%, we're talking closer to 2000 lbs of wet paint to purchase to get the job done.  At around 9.0 lbs/gallon, that's about 220 gallons of paint.  Sherwin Williams sells paint for around \$50/gal, so that's another \$11,000 for the paint.
Then facility costs for electricity and cooling, but I don't have to get into that, as we're already nearing the upper estimate of the per-aircraft cost vasin1987 cited in his answer.

I would guess that certified aircraft paint costs considerably more than paint that we can pick up at Sherwin Williams....

£900'000, apparently, in the case of the Royal Air Force's Airbus A330 Multi Role Tanker Transport.
I know it's not exactly an airliner.
For reference, this is what a paint-job costing a little under £1 million looks like (both photos below from BBC News).

It's not clear to me why this particular repainting job should be so expensive. Perhaps it reflects the British Prime Minister's famed ability to obtain excellent value for tax-payers' money on prestige projects.
Here's the plane in its original livery:

I am not a military aviation expert, so I cannot say whether it is a good thing for a dual-use air tanker to be made more conspicuous.

Although I'm sure it makes for an entertaining story, the £900,000 wasn't for simply a paint-job, but rather the budget for a major overhaul of ZZ336.  "The paintwork concludes a refurbishment stemming from the 2015 SDSR [Strategic Defence and Security Review]... this was a complex engineering project requiring detailed drawings which were developed by AIRBUS. Marshall Aerospace and Defence Group were then chosen to deliver the project on time and within budget." https://ukdefencejournal.org.uk/new-paint-job-for-uk-government-voyager-aircraft-revealed/

@PartyArk Do you know what else was included in this "complex engineering project", unrelated to the paintwork?

Totally off topic: Isn't ZZ336 an unusual registration for a British aircraft? Of is that its military tail number and that doesn't follow normal national registration standards?

The cost depends on a lot of factors, how many planes, how many colors, how desperate the manufacturer is for your business or if you have your own paint shop.
But given the care that must be taken to use the correct paint, the correct solvents, dispose of everything and the FAA requirement that the paperwork for the job must weigh more than the paint - I'm guessing several $10K.
Boeing have some data on the amount of paint and if you should paint or polish including the fact that the paint scheme on a 747 weighs nearly 0.5Ton

Interesting, but around here we generally ask for a higher standard of proof than a guess.

In the airline business you will probably find everything from airline A who got it for free from Boeing in the hope of a big order to airline Z whose own maintenance dept billed them $1M as a tax loss - and everything in between

Not an expert  far from it, though have inspected large aircraft paint finish for Government contract job and £84million hanging on the outcome, once. It is a specialised area, much stripping, pre-treatment, tie-coats, preparation, not your average paint and partial stripping of components may well be required. It feels like, say £900,000 for a multi-colour finish, might be something of a bargain. A previous comment suggested weight gain about 550 lbs (American?), sounds reasonable, but factor in stripping losses first. Specialised labour, working at heights, safety regime, security requirements, safe disposal of waste, it's a big project so project management team and large facility,  (American?)it all adds up. Hope this is helpful and not pompous.

Could you include a few more data points? At this point the answer is a bit thin. Pretty sure that isn't classified or anything.

Welcome to [Aviation.se]! You bring up some excellent points. If you could include a bit more detail as @Therac mentioned and [edit] your post to improve the formatting so it would be more readable, that would be great! Also, if you'll take the [tour] and browse through the [help] that will help you get the most out of (and give your best to) the site.

I don't know where you come up with these numbers. I'm a 20,000 corporate pilot and also an aircraft broker dealing in corporate aircraft sales. A Challenger 605 or 604 which is a 10 to 12 passage plane cost from \$120,000 up to \$180,000 for the better shops. I have had several painted over the years with recent quotes in the last 60 days in July 2019 and the lowest price was \$120,000. A 777 would take 10 times as much paint alone.

Welcome to Aviation.SE! Your answer currently reads like a comment on the other answers. Could you rephrase it to make it into a standalone answer?

If you simply started with "I'm an aircraft broker..." this sounds like a very good answer. The bits before that don't add much to an answer, and do make it sound like a comment. Please feel free to [edit].

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


text:
What exactly is a UK IMC rating?
In chat, falstro mentioned the "UK IMC rating" and described it as "a lighter version of an instrument rating, allows enroute IFR, but no approaches or departures" (although to be fair he also said that he isn't familiar with the exact definition).
The name "IMC rating" implies that it allows flight in IMC, not just filing IFR in VMC for procedural reasons. But if so, and if approaches are not included, then it seems like it would allow a pilot to fly into IMC with no safe way out again if an emergency required an instrument approach.
So what exactly is a UK IMC rating, what does it not allow that a full instrument rating does, and what is the advantage of having it?

From your description, it sounds like you would still have to have VMC at your arrival and departure fields, but that you'd be allowed for fly through IMC en-route.

Falstro's referring to the european en-route IFR rating, not the UK IMC rating. The UK IMC rating (I have one) is a national rating which allows departures, approaches and flight in instrument meteorological conditions, albeit with higher minimums. It can only be used within the UK, not including the channel islands, which means once you leave UK airspace you are no longer allowed to use it.
Training for it is a similar curriculum as any other instrument rating:

NDB and VOR tracking
Partial panel
Unusual attitude recovery
ILS, VOR, NDB, and Surveillance Radar approaches

The reason for the UK rating is to give private pilots an attainable instrument rating option as the EASA one is aimed at commercial pilots and has a huge amount of unnecessary material and training requirements. This is supposedly being worked on but given it's the EU I'm not holding my breath.

I've edited my answer to incorporate your explanation that this is not the UK IMC rating, but EASA EIR. Thanks for pointing this out!

This is also know in Europe as an Enroute Instrument Rating or EIR, which allows flights under Instrument Flight Rules in the cruise phase, but not for departure or approach. It is based on EASA FCL 825

FCL.825 En-route Instrument Rating (EIR)
(a) Privileges and conditions.
(1) The privileges of the holder of an en-route instrument rating (EIR) are to
  conduct flights by day under IFR or in IMC in the en-route phase of flight, with
  any aeroplane for which a class or type rating is held.

The curriculum to obtain an EIR is lower than for a full Instrument Rating (IR), especially the number of hours for theoretical and practical instructions have been lowered:

(2) instrument flight instruction.
  (i) The instrument flight instruction for a single-engine EIR shall include at
  least 15 hours of flight time by reference to instruments.

As GdD has pointed out in his answer, this is not the same as the UK CAA IMC Rating. See his answer for more information on this.

The advantage of having it is that is enables more pilots, due to the lower barriers to obtaining the rating, to fly IMC, for example "on top", if caught out by unexpected weather which has been a consistent killer of PPLs, particularly due to CFIT.
It also opens more opportunities when weather en-route would otherwise prevent a flight and, can provide a more comfortable flight with higher altitudes and guaranteed separation.


text:
In an emergency, how much runway does an A320 need to stop safely?
From time to time I land at Wellington Airport in an A-320.
The runway has sea at either end and is 2,081m (6,827ft) long.
There's never been a problem but I find landing there a bit nerve wracking (the frequent high winds in the area means just getting the plane over the fence is sometimes a little more exciting that most would prefer).
I imagine that getting the wheels onto the runway as soon as possible is a priority so you can start braking but I wonder in a flat out emergency how much runway does an A-320 need (full of passengers/cargo but not much fuel) to stop if nothing else matters but stopping ?
EDIT: I meant to say I do appreciate that wet/dry runway and head wind strength would influence this quite strongly but I'm just looking a ballpark figure.

Just to clarify, are you a pilot or a passenger in this context?

You mean Emergency landing or stop the process when taking off like the latest BA2276 case?

@GregHewgill : I'm a passenger and an admirer of the pilots who land at Wellington ;-)

@Him I'm interested in landings. The question was sparked by a landing the other night when we seemed to be a surprisingly long way down the runway before we got the wheels on the ground and then there was a good deal of brake/reverse thrust noise. It left me wondering how far down the runway could you be and still not end up in the sea. On Sunday night there was a good strong southerly so I guess that changes the nature of thing as well.

Every flight I have been on has used thrust reversal and it makes a huge amount of noise. How much traffic does this airport get. I live here in Denver about 15 minutes away from the airport, and I so wish I could go plane spotting here. An airplane lands like every 45 seconds.

@Ethan Yes thrust reversers are standard for jet landing at Wellingtons. They just seemed a bit noisier than usual on Sunday night so I wondered whether they'd used them to a greater degree / power than usual. Traffic levels at Wellington are pretty low - maybe 30 jet departures and 30 jet arrivals per day ? Because of NZ's location relative to Australian east coast there is a clump of ex-Aussie arrivals around midnight and a clump of departures for Aussie between 6AM And 7AM and they can be noticeable from a noise point of view if there's not much wind.

Can help understanding the terminology used for landing distances.

The answer is pretty broad and is based on the landing weight, runway condition, surface winds, field elevation, density altitude, etc.  you would have to consult the performance charts for the A320 to make this determination for the airport and day in question.

Airbus's charts for the A320 suggest that it requires approximately 4,500ft for a sea-level landing at typical landing weight. I've extracted this from this Airbus document (the A320 landing chart is on page 49), which is admittedly more of a promotional brochure than an operating manual.
Wellington's runway is 5,955 ft between thresholds, and 6,827ft overall, so there is some room for error. However, depending on the nature of the 'flat-out emergency' a pilot may approach faster implying a longer landing roll, or choose a firm landing and significant abuse of the brakes to shorten it.
Christchurch and Auckland airports both offer much longer runways at 10,787ft and 11,925ft respectively, so I'd speculate that a pilot faced with a known problem with brakes or thrust reversers might elect to divert there if range permitted.

From QRH, via this document, question 73: A320 – CONFIGURATION FULL, LANDING DISTANCE WITHOUT AUTOBRAKE Actual Landing Distance, GW 130,000, Dry: 2,920 feet This is the ALR determined during flight tests, security and failures coefficients apply. Note that landing distance is usually measured from a height of 50 ft to the wheels stop.

The Airubs web also has a document titled “A320 for airport planning” which is a technical document and it does have landing field length chart, which confirms 4500 ft at sea level at MLW for A320-21x (CFM56 engines) and a little less for A320-23x (IAE V2500 engines). The older edition also had approach speed graph, but the current one only has the value for MLW.

Note, that landing distance calculations don't consider thrust reversers. The difference between engine types is likely due to difference in idle thrust rather than efficiency of reversers. So problem with reversers is not an issue. Problem with brakes would probably warrant diversion.

Related details showing the complexity of distance calculation: In flight landing performance. Landing distances for A320 extracted from Airbus OLD with landing distances for different conditions, and using two definitions of landing distance: Operational Landing Distance (OLD) and Factored OLD (FOLD).


text:
Apart from the C-130, are there other airlifter aircraft that are able to perform LAPES drops?
The C-130 is well known for her ability to perform a LAPES (Low Altitude Parachute Extraction) drop to deliver vehicles to an airhead.
I'm wondering if other larger military airlift aircraft that are also able to perform this maneuver, in particular the C-17, or (unlikely) the C-5?

Pretty sure the C-17 does.

I'm pretty sure I once saw a clip of some RuAF aircraft doing this, but cannot find it right now. I'll try to find it, but a priori I don't see LAPES requiring anything but a very stable aircraft that does not pitch hard the moment the cargo is deployed.


text:
How prevalent are HUDs in civilian aircraft?
Head-up displays (HUDs) seem to be a must in modern war aircraft, and have been for quite a while.  This is not much of a surprise for an aircraft flown by a two- or, often enough, one-person crew who has to fly the aircraft, or rather, a flying weapon system, into an unknown mission into a hostile area, not just flying the aircraft in higly dynamic maneuvers, but also operating a wide array of offensive and defensive weaponry.

Now, HUDs are certainly available for all kinds of civilian aircraft as well.  Earlier, we learned that while they are ceratinly availlable for light GA aircraft, their cost keeps the number of installed system on such aircraft down.  For the sector of corporate jets, and certainly for the big airliners, HUDs are often available as a factory option.

What I'd like to know is:  How prevalent are HUDs on civilian aircraft (we heard of light aircraft earlier, so we can exclude them here)? And what is the current trend, have they proven to be effective? Do they increase safety, do they reduce workload on the flight crew?  And if so, will we see more HUDs installed on aircraft in the future?

One element of answer in  Which airlines did use a HUD for their A380?. China requires a quota of HUD by airline (100% in 2025, domestic only), in order to speed up airport operations.

The 2015 question is from an older era. Today, you can get one straight from Garmin, the GHD 2100. It has first flown on the Cessna Longitude in 2017. That's a business jet, but definitely not an airliner, where HUDs are gradually becoming the norm.
This is a projection HUD, like military and commercial ones, and appears to use a proper combiner glass, allowing to to be focused at infinity, removing the need for eye refocusing between the HUD and the terrain.

As to the effectiveness of HUDs in general aviation, the opinions differ. The most authoritative should be the 2009 FSF study, which labeled them a safety improvement. This article discusses the findings in a broader light.
The study's conclusion was that a set of measures, including a HUD, displaying data from angle of attack sensor (or rather three such sensors, as we've painfully learned), TCAS, could have improved the odds in as many as 38% of accidents.
A tougher question is whether a HUD would be useful in a light GA aircraft without all of the sensors considered by the FSF in their study. Some studies have measured a considerable risk of the pilot missing objects during the transition from symbology to normal vision, which increases for dim objects. It follows up on past NASA research that shows HUD-to-world transitions to take additional time and can divide the pilot's attention.
So there is some evidence that HUDs might have detrimental effects for VFR flight, particularly in marginal VFR or night VFR, but it's nowhere as authoritative as the FSF's unambiguous endorsement of HUDs for commercial aviation. Both studies above were more of the conclusion that HUDs should be redesigned in a way that better blends in with the real world, rather than avoided.
The Garmin example with synthetic vision on clearly isn't such a redesign, but the Longitude isn't a VFR airplane either. In fact, Acuario's home-made example might be closer to the minimalist display practical for light GA in VFR.


text:
How and when are cockpits cleaned?
It's well known that cleaning the cabin of an airliner in the short time it is on the ground can be a challenging task for the cleaning crew.

But what about the best seats in the plane, the cockpits? Are they cleaned on the same occasion? Is there a specially trained cleaning crew? Do pilots sneak in a damp microfiber cloth and wipe down the handles of the thrust levers, the switches and the displays?  Do seats and the carpeting ever get treated with a Kaercher Carpet cleaner (or that of any other reputable manufacturer)?

These anecdotes aren't authoritative enough to extract real answers from, but they sure hint at the wide range of attitudes about this topic!

Another anecdote, a friend of a friend worked for Delta maintenance in Atlanta and I got to tour a 777 that was in the hangar, including the cargo bay. Interestingly there was a computer terminal in the cargo bay used by maintenance people where they can log stuff or change settings similar to one that maintenance (and pilots) use in the cockpit. But anyway I got to sit in the captain's seat and I was surprised to see that there was grime on several of the flat surfaces, as if the cockpit had not been thoroughly cleaned in a while. Presumably pilots are used to it and are not bothered by it.

While this may not happen frequently for some operators, this is recommended by The WHO Guide to Hygiene and Sanitation in Aviation available at ICAO.

This is part of ground handling. This includes seats, floor and windows, as well as stowage areas and racks. IATA, the operators syndicate, recommend to have cleaners entering the flight deck supervised by a person authorized by the operator (example). Cleaning hardware and products are selected in accordance with the manufacturer recommendations. The frequency is daily (✔), and when requested (+).
During COVID pandemic there was a special IATA/ICAO guidance for extended disinfection of the flight deck.
Panels (instruments, switches, lights, etc) and controls are not cleaned. Cleaners are not allowed to touch or move them, incidents must be reported to the operator.


text:
Where can I find the flight path data for the Russian spy plane that flew over the US on 9 Aug 2017?
Multiple news outlets are reporting that a Russian spy plane, a Tupolev Tu-154M, flew past various locations in the U.S.
Politico is reporting that the plane was seen on a flight-tracking website in Washington D.C., Bedminster, NJ, and Dayton, OH.
Is there a way (maybe on the flight-tracking website Politico mentions) that I can look up historical data on this flight to see when it was in each place and what its flight path was?

Without knowing departure or arrival airports and times... FlightRadar24 has a playback feature.

@abelenky: The details of the observation equipment are actually specified in the treaty, and every airplane must pass certification. All sensors used must be commercially available to every signatory. There will also be an official representative of the observed party on board. (The treaty even allows the observed party to choose whether the observing party is allowed to bring their own plane or must use one provided by the observed party). They might be secret from the general public, but not from the signatories of the treaty. I.e. Russia knows exactly what is in the US plane and vice versa

More details on the treaty here: https://en.wikipedia.org/wiki/Treaty_on_Open_Skies


text:
How often is QFE set on an altimeter during flight?
In countries that use QFE rather than QNH (such as China), how often will a pilot set the QFE setting on their altimeter during flight? Is it only when they intend to land at an airfield, or does it get set for the nearest airfield/aerodrome and updated when entering a new airfields's airspace?
I understand that in the US, QFE is primarily used for airshows and aerobatic competitions, which are presumably operating out of a single airfield and therefore wouldn't be changed in flight.

@ymb1: There is only one answer that includes this topic, and this is not the selected one.

Which kind of aviation? GA?

I'm primarily interested in GA I suppose, as I'm curious how often a pilot would physically set their altimeter(s) to the appropriate QFE setting.

But I would be interested in commercial aviation answers too. A separate but similar question would how often pilots in these conditions would switch between say QNE and QFE in flight.

For what it's worth, the only times I used QFE in 30 years of flying was when going into Khabarovsk, Russia in the 1990s. When cleared for the approach, they would give us QFE, and we would then set it in our altimeters.

so you flew either QNE or QNH up to the point that you were cleared for approach and were then given QFE for the field?

@ymb1 Not remotely a duplicate. What is being asked here isn't being answered there.

+1 Great question, I never knew there where two types of altimeter settings.

To answer the question for the UK; once at most.
In the UK, QFE is used in the circuit by 65% of pilots. It may be given to you when you first contact the tower, whether you ask for it or not.  Most of the airfields in the UK are within a couple of hundred feet of MSL, so I'll sometimes set it on my second altimeter when I'm coming into a field that is unusually high, just as a reminder.
RPS now, that really is  useless.

To add some more context - most pilots will only dial in QFE when either knowingly staying in the circuit (for practice/testing/whatever) or when the landing airfield is in sight.

You don't use QFE or QNH in an airspace, you use it for a purpose.
QFE is rarely used in the US, other places in the world it's primarily used for landing, although that's personal preference (I use QNH). You set QNH on the ground at your departure airfield using the local setting then update QNH on route, when approaching an airfield for a landing you would use that airfield's QNH setting as given to you over the radio or from an information broadcast.
The only time I could see setting QFE more than once would be in the case of a diversion, if you needed to fly to another airfield you'd need to go back to QNH, then set the local QFE at the other airfield. This is extra workload and could be a forgotten step, which one of the reasons I prefer QNH for landing - it's one less thing to do.

Is QFE a thing of the past, in countries where it was commonly used? I think Europe GA pilots used it often for landing and local flying.

my understanding is that China still uses QFE. Russia is moving towards QNH according to this article (dated Feb 2017): http://flightservicebureau.org/big-change-russia-finally-moving-to-qnh/

It's still very commonly used in western Europe by GA pilots when landing @mins, I don't know about the big boys though. The UK still uses overhead joins, which is archaic IMO, but I guess if it ain't broke....

What's the difference between overhead join and, say French airfield pattern integration, which if I'm not wrong is at the crosswind or downwind leg? Is this worth a new question?

The French joining procedure is the same as the UK one as far as I know @mins. I haven't done it much there as I almost always have flown into towered airfields and been sequenced in.

95% of all airports in China are now "QNH" qualified, except some small military airports, thus we don't use QFE most of the time.


text:
Would it be beneficial to have rotors AND propellers instead of a tiltrotor?
Would it be beneficial for tiltrotor aircraft if they had BOTH rotors and propellers, instead of the hybrid proprotors that are neither good propellers nor good rotors?
Like imagine the V-22 Osprey with additional propellers for example mounted on the wings, which are turned off in helicopter flight and when the airplane transitions into airplane mode, the turbines switch from powering the rotors to powering the propellers via transmissions and the rotor blades pitch to an angle where the drag is reduced. Then the plane would be only powered by propellers, which are better for airplane flight and could achieve higher speeds. Would that be possible and if so, why has nobody tried to do this?

What you describe is effectively a "compound helicopter" -- an inefficient design used only when you must combine hovering flight with maximum forward speed -- but with hovering managed by tilt rotors (adds complexity and weight for the shafts and transmission) and lift in forward flight handled by the fixed wings.
The simple reason this hasn't been built is the certainty that such as chimera won't do any of the things you want to do well.  It will be too heavy, so will require more power to hover and need to fly faster to transition from hover to forward, it will be so complex as to be extremely expensive and lose reliability, and there's no use case for the very slight (if any) gain in performance vs. conventional airplanes, helicopters, compound helicopters, or tilt rotors.
It's like building a power tool that does the job of a table saw, lathe, router, shaper, and planer -- it'll wind up costing as much as the combination, require considerable time to switch from one application to the next, and won't do any of them as well as dedicated machines -- all you save is space.

There are 2 major problems. First is the weight you'd incur from:

Extra rotors/propellers
Transmission components (the V22 already has a transmission in case of an engine failure, it's already more complex than you'd ideally want but it's necessary for safety)
Structural components to support the forces from the propellers and extra transmission

It's lighter to turn the engine and rotor together, and probably more reliable.
More importantly the rotors have aerodyamic issues at higher speeds. Remember the rotors are still up there, and they must be dealt with. You could:

Fold them away or back: you'd need a mechanism capable of stowing and unfolding the rotors in an airstream, which means weight
Have them produce no lift: this means they will be dead weight so they will take away from payload
Use them for lift: this would be similar to a gyrocopter, where a rotor is unpowered but produces lift from forward flight. There's aerodynamic limitations due to the differences in lift from advancing and retreating blades which would limit your top speed

Such a design may be beneficial as it lends itself to simplification.
Power divided between a fixed pitch rotor and fixed pitch propeller using differential gearing (as in the rear wheels of a car) would, by the momentum theory, shift power from lifting to forward propulsion in such a way that the rotor would automatically be kept in a near horizontal attitude at nearly all speeds, maximizing L/D.  A separate propeller and rotor would avoid the Osprey's tilt rotor size compromise, contributing to efficiency.

Just ask the people at Fairey how well their Rotodyne succeeded.
Wikipedia article
Overly complex, heavy, and expensive.


text:
Are there any standards for defining your own ARINC 429 labels?
Is anyone aware of any ground rules or best practices for defining your own ARINC 429 labels? Are there certain ranges of labels that correspond to groups of parameters like engine temps, rpms, etc?  Am I basically free to start at Label 000 and define my own words?

What is your need for new labels? Do you have an existing ARINC compatible product that you just want to add some labels to an existing bus? Define a new output bus with new data? The point of ARINC is interoperability. Unless you are building both ends of the bus, you should be working with the relevant AEEC committee. If it’s a standalone project that won’t ever connect to an external product, you can do pretty much what you want.

Appendix E of the ARINC 429 Part 1 spec dated 2004 provides the guidelines for label assignments such as:

label ranges for BNR/BCD/Discrete data
Maintenance vs normal data

Label 000 should not be used and label 377 is reserved for the Equipment Identification.
What ultimately matters, however, is that the receiving equipment knows how to decode the labels it receives.

I have a copy of the ARINC 429 Part 1 spec dated 2019, and it does not have an Appendix E. Is this in a different Part of the specification?

I don't have access to the 2019 version, but in the 2004 version it is in ARINC 429 Part 1


text:
If an aircraft diverts to another airport for mechanical reasons, does the dispatcher create a new flight plan?
Let's say the aircraft is flying from LEJ (Leipzig/Halle Airport, Germany) to DXB (Dubai International). And enroute if the aircraft needs to divert over Turkey to land because of one engine failure, what will the dispatcher do with reference to giving a new flight plan from the point of diversion over Turkey to new airport?
Will a new flight plan be executed and provided to the flight enroute? And what will be the plan if the landing weights are exceeded to the diversion alternate enroute?

The purpose of an IFR flight plan is to tell the controllers where the plane wants to fly. Once the pilots start talking to the ATC and get their initial clearance, the routing can be amended any time by ATC, whether on pilot request or for other operational reasons, and this is just coordinated among the controllers and entered in their system.
An engine failure is an emergency, so the controller will mark the aircraft as having an emergency in the system, and might update the destination in the system. But even for diversions that are not emergency, the controller just updates the data in the system. No need to involve the dispatcher. Even if it is actually the dispatcher requesting the diversion—sometimes something fails on the airplane that allows it to fly on, but because fixing it in the original destination would be difficult, the dispatcher asks the plane to return to base or another hub and arranges different plane to complete the flight—but they still don't file another flight plan, just tell the pilots to request return to base and pilots handle it with ATC.

No, there's no new flight plan created for the diversion. An engine-out is an emergency situation, the pilot takes whatever action they feel is needed to save the plane, and the paperwork can wait until they're safely on the ground.
If the plane is overweight for the landing, then, again, the pilot is in charge of deciding how to handle it. If they decide it's safe to do so, they can fly around burning or dumping fuel until they're at a safe landing weight. If not, then they'll just land overweight and hope that they can stop the plane before it reaches the end of the runway.

Landing performance data includes overweight landing cases, so stopping distance would be a known, not a "hope". The main consequence of the overweight landing would be maintenance inspections of everything that might be damaged, even though such damage is quite rare.

Since an overweight landing due to an inflight mechanical emergency will require inspection/repair of the malfunctioning equipment, the time spent doing the overweight landing inspection/repair would probably happen simultaneously and probably not significantly delay the aircraft's return to flight.

Dear Freeman, Thanks.. please advise what a flight dispatcher
needs to  do if any onboard equipment becomes inoperative or unserviceable      for an Enroute flight with reference to navigation, and communication procedures including the release or continuance of a flight.

@XavierMendes I'd advise that you ask a whole new question.

I’d advise that you stop asking homework questions.


text:
What does a dispatcher do if an aircraft can't stay on a NAT route due to a communications failure?
For example, a flight is enroute form from LEJ (Leipzig/Halle Airport, Germany) to MIA (Miami, USA) on a North Atlantic Track (NAT). Now suppose there is an issue with the communication or CPDLC of the aircraft which is a mandatory requirement flight over the North Atlantic.
Now what back up plan will the dispatcher do with reference to an updated flight plan? The aircraft cannot fly the NAT level and have to drop down to a lower flight level.

Why would the plane not be able to fly the NAT level, or had to drop to lower flight level?

https://www.faa.gov/air_traffic/publications/atpubs/aip_html/part2_enr_section_7.8.html

Hi Jan , thanks a lot..  Since its mandatory to have CPDLC and communication with the ATC over the North Atlantic.  If the CPDLC fails there will be no communication with the ATC. Will it still be OK to fly the track with  no communication.. and what  is needed to be done by the Flight dispatcher when the  flight is enroute..

Every flight within the NAT region is issued with an oceanic clearance that includes routing, altitude and speed. In case of communications failure the aircraft shall adhere to the last acknowledged clearance. The clearance ensures a conflict-free crossing of the Atlantic.
Besides mandatory CPDLC there is a requirement to be able contact ATC via radio operators using long-distance HF radios, and if flying well north of the track system using VHF relays in Iceland and Greenland. One can also use other aircraft in the Atlantic to relay messages should both CPDLC and HF fail. On top of that as a last resort it is possible use satellite telephone if AC is equipped with one. But basically, after entering the NAT region with an oceanic clearance it is possible to cross the pond without talking to anyone.
To answer your question: the flight dispatcher plays no role in case of communication failure. Indeed, if the plane is able to contact dispatch it is very likely it can contact a radio operator or ATC.


text:
Where should vortex generators be positioned on the chord line?
Where is the best place for vortex generators? Maybe at the place where airflow speed is highest to induce strongest vortices?

The ideal location is normally identified by experimentation for a particular wing, but is usually just forward of the transition from laminar to turbulent flow when approaching stall AOA.
You want the VG to be in smooth air to create a proper vortice, so it needs to be clear of the turbulent boundary layer.  On the other hand, too far forward wastes energy, so there is some chordwise sweet spot, say between 5 and 20% of chord, that you have to figure out.
The maker of the VG kit will work out a preliminary location by computer simulation or by tuft testing, then install the kit on their representative test aircraft with tufts on the wing behind the VGs, and go fly while filming the tufts to observe the results.
If I was going to put VGs on the roof of my car like your other post, I would just tape tufts to the roof and back window and have someone record the tuft behaviour while driving. They will show the flow separation point pretty well, and you would stick your VGs just forward of that.

At what angle VGs are generally  install?

I believe it's 15 degrees off the longitudinal axis.  If you find decent pic looking down at a VG set you should be able to measure it more or less.


text:
What’s the NCVA at the end of the F135 engine?

What’s NCVA at the end of the F135 engine? And what does it do?

NCVA: Nozzle cooling valve actuator.
It allows a cooling flow to enter the nozzle. From Wikipedia:

In this configuration most of the bypass flow is ducted to the wing nozzles, known as roll posts. Some is used for cooling the rear exhaust nozzle, known as the 3-bearing swivel duct nozzle (3BSD).[37] At the same time an auxiliary inlet is opened on top of the aircraft to provide additional air to the engine with low distortion during the hover.[31]

Source

"Valve" or "vane"?

@OrganicMarble: Thanks!! Vanne is a French synonymous for valve...


text:
Does a green card holder need TSA approval to take the FAA knowledge test?
Do Green Card Holders need approval from TSA to start ground school and take the FAA knowledge test? Or are they allowed to take the test before they apply for fly training?

The TSA only regulates flight training, per 49 CFR 1552. That's defined as "instruction received from a flight school in an aircraft or aircraft simulator". There's no TSA approval required to take a written test, or for ground training. The FAA requirements are listed here.
I suppose it's possible that if you want to do training at a large school with integrated ground and flight training (probably under part 141), they would require TSA approval as a pre-requisite for starting the course. In that case it would be a school requirement, though, not an FAA or TSA one.

Good question! Permanent residents need to create a profile in the Integrated Airman Certification and Rating Application (IACRA) System, prior to taking an FAA Airman Knowledge Test. Creation of the profile will provide you with a Federal Tracking Number (FTN) that you will need to take an FAA knowledge test.
Source: FAA Airman Knowledge Testing Matrix

Getting an FTN from IACRA applies to everyone. The question is whether there’s any approvals specific to an LPR.

@StephenS The letters "LPR" are nowhere in the question, therefore that is not the question.

Green Card Holder = LPR

You could also cover the difference between starting ground school and taking the knowledge test.

The question is whether TSA approval is needed. The answer is "No."


text:
Why aren't the canards used as airbrakes on the Tupolev Tu-144?
The Tupolev TU-144 uses retractable canards to stabilize the aircraft while starting and landing. On this picture you can see them very well:

Source: AirlineFan.com Copyright: VOLPATI
It doesn't have reverse thrust and air-brakes, and relies purely on very strong wheel brakes. Wouldn't it be possible to rotate the canards by 90° (after touchdown) in order to create a very large air-brake? I don't think it would need too many modifications to the current form of the canards.

I guess the whole effort to make them rotate and to transfer the new loads into the structure were adding too much weight. I would expect that Tupolev engineers looked into that and dismissed it.

No problem and well done, @Spypsyduck. I added the note that the picture is copyright. It looks like the exact same picture is on Wiki (linked in the text), credited to the same person and released under a GNU copyright, as well, so we're probably safe in using it, may just need to change where it's sourced from if the mods feel that's necessary.

@FreeMan Released under a GNU license. Copyright is the right of the originator of a work to control how it is used; a license is permission to use.

Oops, thanks for the correction, @DavidRicherby.

Sorry about this (most likely) newbie-question, but where did some of the comments (including my own) go? I did not delete them, but I also haven't received any notification that somebody else deleted my comments.

A number of things happen when you rotate the canards by 90°, and in no way I see how these could be addressed by

not too many modifications

1. Transient
Once you land, you need a certain amount of time to rotate the canards. During this time the canards will not produce a perfectly horizontal force, but it will have also a vertical component.
Whether this component will be upwards or downwards it will depend on the rotation direction: rotate them with the leading edge up, and you will have some upward force; downward otherwise.
In both cases this is not ideal:

an upward force will reduce the adherence of the nose wheel, reducing the steering authority
a downward force will increase the load on the wheel, increasing the chance of tire burst and increasing the required size of the strut to sustain said load.

2. Deployed Status
Let's assume for a second that the transient problem can be avoided. Now you have two large surfaces perpendicular to the airflow that create a massive amount of drag. And torque.
You need then to design a structure that is capable of:

keep the canard in place during the flight
rotate the canard by 90°
sustain the drag force during deceleration
sustain the torque during deceleration

You can reduce the torque and drag forces to be transmitted through the mounting by delaying the deployment/rotation of the canards, but that would defeat the purpose or, at the very least, severely limit the usefulness of such a system.

In conclusion, a structure that would fulfill all the listed requirements is

extremely likely to be heavier than equivalent brakes,
more likely to be prone to structural problems due to complexity,
more expensive due to maintenance,

making even less sense in an aviation application.

Would the stopping distance perhaps increase instead of decrease from using the canard as an air brake?  My career involved stopping performance calculations for conventional airliners rather than delta wing configurations, but it seems that with existing landing technique you are getting a lot of drag benefit from the angle of attack of that big inefficient delta wing while the nose gear is still in the air.  Maybe more drag than there is to be had from getting the nose on the ground relatively quickly so that a smallish canard can be rotated? To come out ahead, it might be necessary to have the canard air brake activate prior to nose gear touchdown.  That would likely require automated real-time adjustment of the elevons to counteract the transitory moments, and perhaps a non-90 degree canard deployment angle during rollout to reduce the undesirable  moment coming from a drag force well above the vertical CG.
Even if it happened to be the case that the canard was already capable of being rotated to any desired angle, given all of the above considerations something like slightly bigger drag chutes would presumably be a much easier way to get the same result.


text:
How can the landing gear fit in the small room in the engine bay on the Tupolev Tu-144?
I recently went to the museum in Sinsheim, Germany, where a Tupolev Tu-144 is on display. I noticed that the landing gear of this plane is actually way wider than the space it has available when retracted. How can this work? Does the gear fold before retracting?
Sadly, I wasn't able to find any video footage of the TU-144 retracting its gear. Please take a look at the picture I took to understand what I mean:

google image search for 'tu-144 landing gear' gets some pretty decent explanations, did you try searching before asking here?

And now this very question is search result number 4 on Google, and will likely move up higher now that it has a couple good answers. I don't see any problem with asking on-topic questions that have easily found answers on Google, it helps build up Stackexchange as a knowledge base and helps with self-referential answers, so when someone asks "How can landing gear that's too big fit into the landing gear bay?", the answer can link to this answer instead of having to link to external sources that may not always be available.

The Tu-144 uses much smaller wheels than comparably-sized subsonic aircraft. This makes it possible to rotate the gear bogie sideways towards the middle of the aircraft, so it can be stowed vertically inside the wheel well. Your picture already hints at that:  Note that the gear strut is offset inside the wheel well, so it would leave more space on one side for the gear bogie.

Tupolev Tu-144 landing gear (picture source). Note the big drums of the wheel brakes: They were needed to stop the aircraft - the engines had no thrust reversers! Inside are stacks of disc brakes to absorb the energy that comes with a landing speed of 270 km/h. Also note the unusual sideways arrangement of the scissors link: This way it did not interfere with the rotated wheel bogie. Next clue: The big hydraulic cylinder on the left was used to pivot the bogie around an axis parallel to the direction of flight.

Picture of a photo from Tu-144 landing gear test, including finger print (picture source). This shows the gear in mid-sequence: The bogie is already rotated and lies sideways, with the gear strut between the wheels. Now the strut pivots forward and up into the wheel well.
Requiring complex motion adds more failure modes: On its 59th flight, the XB-70A suffered a malfunction of the left gear which left the bogie in the upright position. If you want to know how it was supposed to work, watch this video from 14:47 on. The picture below is taken from this video.

What do you mean when you say "including finger print"?

@DavidGrinberg: The picture is of an old print. It shows the reflection of a lamp on the top left and a finger print on the top over the gear doors. Also, the lower edge is warped - the print was not lying flat when it was digitized.

The Tu-144 landing gear rotates 90 degrees when retracted up between the engines.

Source: Tu-144 Landing Gear Retraction

Source: Tu-144 Landing Gear Retraction

That actually worked?.... Oh, those Russians...

@OwenBoyle Even the guy in the middle looks skeptical

The North American XB-70 also had a very strange method of gear retraction:  https://www.youtube.com/watch?v=0d6VmbwOoek

XB-70 gear swing:  https://youtu.be/seWJa6SG3LQ?t=4m48s

Please tell me this gear retraction process is only the first step in reconfiguring the aircraft as a giant humanoid robot.

The nose and canard wings are movable too... :)

authors: Михаил Голодняк


text:
What are these unsymmetrical parts at the tail of the Tupolev TU-144?
On a recent trip to the Technikmuseum Sinsheim, I noticed that the back of the Tupolev TU-144 is not symmetric.
Please take a look at the picture I took to understand what I mean:

(Please don't mind the crane, the Tupolev was getting cleaned that day)
Those parts most likely serve some aerodynamic/stabilizing purpose, but what exactly do they do? Why aren't they the same on both sides?

The four parts you're referring to contain the actuation mechanism for the rudder, similar to the wing pods that contain the flap actuation mechanism.
The reason they are not arranged symmetrically is that the rudder has two sections (you can see the 'cut' in the middle in your image)- apparently to provide redundancy and improve safety. So,each section has two actuation mechanisms on the same side, with both of them in opposite sides.
The Concorde had a similar arrangement, albeit with only a single mechanism on either side, as can be seen below.

By Simon Boddy, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=31619795

I think the split rudder is more so for the high loads imposed on the control surfaces at higher speed as well as reducing the control authority, see http://aviation.stackexchange.com/questions/8432/what-is-the-advantage-of-the-two-part-rudder-and-how-does-it-work for a larger discussion on split rudder design.

@RonBeyer That might also be a reason. But the Concorde atleast had a bad habit of losing its rudder rather often.

@aeroalias I love how that article shrugs off structural failure of a control surface at mach 1.8 as a "non-event."

@TomMcW: Well, said control surface happens to be one that isn't used at all in normal cruise flight, so...


text:
Are there 5000+ companies with IATA (two-character) codes?
From Wikipedia > List of Airlines

There are around 5000 airlines with IATA codes.

From Wikipedia > List of Airlines Codes

IATA airline designators [..] are two-character codes [..]

and

after an airline is delisted, the code becomes available for reuse after six months

The last quotation suggests that no two airline companies can share the same IATA code.
Depending on the characters allowed, a two-character codes can make $26^2=676$ combinations or eventually $36^2=1296$ combinations. It would take at least 71 different characters authorized to register 5000 companies ($71^2=5041$). It is unlikely that 71 or more characters are authorized. It seems paradoxical to me.
What am I misunderstanding?

In this list from IATA themselves, there are about 260 airlines with a IATA code.

It's obviously an error in that Wikipedia page. The "5000 airlines with IATA codes" text actually links to:
https://en.wikipedia.org/wiki/List_of_airline_codes
which lists lots of airlines (over 6000), but most of those have ICAO (3 letter) codes, but not IATA (2 letter) codes.


text:
How are the system development and integration procedure separated for Integrated Modular Avionics?
I'm reading this paper about IMA (Integrated Modular Avionics) and I don't get the splitting of the development and integration procedure. In page 4 it says:

Airbus has to modify the conventional development processes and responsibilities. The IMA system development and integration procedure is split between

the Avionic Module Supplier
the Aircraft System Manufacturer
Airbus

Who is the Aircraft System Manufacturer? Which is its function?
My doubt is principally about this paragraph that is few lines later:

The open IMA concept puts the assembler into the position of the IMA system integrator. The
  development responsibility for the single systems and their functions remains at the system
  manufacturers. The avionic module supplier provides “empty” IMA modules to both, the
  system manufacturers and to assembler. The system manufacturer applies the CPIOM for the
  local function implementation and qualification. The assembler, in turn integrates the own
  empty CPIOM with the ADCN on the aircraft in order to establish the basic computing resource
  for different system functions.

the company that builds the IMA hardware? building IMA hardware?

You might want to go back and double-check if the paper provides a specific definition for Aircraft System Manufacturer, but otherwise it likely referring to Airbus's suppliers who are responsible for providing any number of aircraft subsystems that Airbus then combines into the final product. The use of such suppliers is very widespread in any manufacturing industry due to the mind-boggling number of components and systems that go into a final product - it would be counterproductive for the final assembler to manufacture all of them internally.

I'm not an expert in this area, but I think that the jist of it is that a particular component like say, a Flight Management System, is produced and manufactured by a third party (Honeywell, Universal Avionics, Collins, etc.) and not by the actual aircraft manufacturer.  For the IMA, it sounds like they are using "generic" hardware which may be used in various industries, which are then programmed by the avionics supplier for their aviation specific functions and then supplied to Airbus.

It sounds like the IMA module is a standardized rack into which Avionic Modules are mounted. Honeywell, Collins, etc. make modules that perform a specific set of functions and put them in a box that will fit into the IMA rack. It's then up to the aircraft manufacturer to select a set of modules and ensure that their inputs are supplied and outputs are handled by other standardized modules or by custom systems within a particular aircraft. The aircraft mfg. will build 1 or more IMA rack spaces into the fuselage as needed to hold the modules for that craft.

The Aircraft System Manufacturer is the company developing the system that is being implemented on IMA hardware (supplied by the Avionic Module Supplier). They will likely develop software to load onto the IMA hardware to perform certain functions.
For example:
Airbus would like to implement a Thrust Reverser Control System for their new airplane. The system would take in some parameters gathered from various sensors within the aircraft, perform the necessary logic and/or calculations, and then provide the necessary control commands to the thrust reversers.
Now Airbus doesn't want to develop this specific system, so they contract it out to another company ACME Avionics. They provide ACME with the System Requirements Data, which describes how the system must operate, what inputs it will use, the Design Assurance Level of the system, and the IMA modules the system must use to implement the requirements.

So we have Airbus that build the plane, the Avionic Module Supplier who supplies only the hardware and the Aircraft System Manufacturer who supplies the software?


text:
What Electronic Flight Display is this?
I just watched this video in which the avionics surprised me. It looks like a half Garmin G600, attached on his yoke.

What is that and is it permanently attached to the yoke or is it portable?
Could it be for aircraft that can not be retrofitted? Because there is also something to see what looks like a ADS-B-receiver to me:

The top unit is a Garmin 696 portable aviation GPS unit on a yoke mount.  The lower is a Stratus ADS-B receiver.

At first this reminded me of the Garmin G3X. However, it is mounted on the yoke and must be a GPSMAP 695 or 696
https://buy.garmin.com/en-US/US/p/14860


text:
Are there any countermeasures for lasers or the people who use them to blind pilots?
Yesterday there has been another laser-incident at my local airport LOWG. The laser hit the cockpit twice, but the pilot managed to land the Dash 8 Q400 safely.
I'm taking this recent event as opportunity to ask, if there are any countermeasures at the time, be it in use already or in development, against these despicable people or their lasers?

I can think of a few active countermeasures, but i'm afraid that those would lead to some serious human rights issues...

Is it possible to blend pilots?

See the answer here:  https://aviation.stackexchange.com/questions/25464/does-the-faa-advise-or-require-pilots-to-wear-eyewear-designed-to-protect-them-f?rq=1

@abelenky Oh, thank you. In German "blenden" means "to blind", so I just used "blend". My mistake.